Hitherto, in the field of medicine and presswork, the waste liquid accompanied with the wet processing causes a problem on the working efficiency. Furthermore, it is strongly demanded to reduce the amount of the waste liquid from the view point of the environment protection and the space saving. Consequently, the heat-developable photosensitive material has been put to practical use and has been rapidly spread in the forgoing fields.
The heat-developable photosensitive material has been proposed a long time ago, for example, in U.S. Pat. Nos. 3,152,904 and 3,457,075.
The heat-developable photosensitive material is usually treated by a thermally developing processing apparatus, so-called a heat developing processor, for forming an image by stably providing heat to the heat-developable photosensitive material. As above-mentioned, a lot of the thermally developing processor is supplied to the market accompanied with the rapidly spreading in recent years. However, a problem is caused that the insufficient conveying of the photosensitive material and the unevenness of image density are caused by the variation of the slipping property between the heat-developable photosensitive material and the conveying roller or the treating member of the thermally developing processor depending on the thermal and humidity condition on the occasion of the thermally developing treatment. Moreover, a problem is posed that the image density of the heat-developable photosensitive material is varied accompanying with passing of the storage time. It has been found that such the problems are considerably posed in the heat-developable photosensitive material which is thermally developed to forming an image after imagewise exposure by laser light.
It has been recently demanded to make compact the laser imager and to make rapid the processing. For obtaining the sufficient image density of the heat-developable photosensitive material by applying a rapid processing, it is effective to use silver halide having a small average diameter to increase the number of color forming point so as to raise the covering power as described, for example, in Japanese Patent Publication Open to Public inspection, hereinafter referred to as Tokkai, Nos. 11-295844 and 11-352627, or to apply a highly active reducing agent having a secondary or tertiary alkyl group or a development accelerator such as a phenol compound, hydrazine compound and vinyl compound.
Recently, it is further demanded to make compact the laser imager, to raise the precise of image and to prevent the increasing of fogging during storage. For example, Tokkai No. 2000-305213 discloses a technique in which no spectral sensitizing dye is used for preventing the fogging during the storage and the exposure is carried out by ultraviolet or blue laser light. Furthermore, Tokkai No. 2003-91053 discloses a technique in which exposure is carried out by laser light having an emission peak within the range of from 350 nm to 450 nm for miniaturizing the apparatus. However, the problem of occurrence of the default of conveying on the occasion of thermal development and the unevenness of image density is posed when the compact apparatus is employed or the rapid processing is applied even when the above techniques are applied. The improvement on the fogging during the storage is also insufficient.